hydrogen peroxide

noun

: an unstable compound H2O2 used especially as an oxidizing and bleaching agent, an antiseptic, and a propellant

Examples of hydrogen peroxide in a Sentence

Recent Examples on the Web
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Let the hydrogen peroxide work for at least 10 minutes before attempting to wipe away any visible mold. Mary Marlowe Leverette, The Spruce, 14 July 2026 See All Example Sentences for hydrogen peroxide

Word History

First Known Use

1872, in the meaning defined above

Time Traveler
The first known use of hydrogen peroxide was in 1872

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Cite this Entry

“Hydrogen peroxide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hydrogen%20peroxide. Accessed 18 Jul. 2026.

Kids Definition

hydrogen peroxide

noun
: an unstable liquid compound containing hydrogen and oxygen and used especially for bleaching and as an antiseptic

Medical Definition

hydrogen peroxide

noun
: an unstable compound H2O2 used especially as an oxidizing and bleaching agent and as an antiseptic

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